Incentivizing Safer Sexual Behavior: Evidence from a Lottery Experiment on HIV Prevention

Abstract

We investigate the effect of a financial lottery program in Lesotho with relatively low expected payments but a chance to win a high prize con- ditional on negative test results for sexually transmitted infections. The intervention resulted in a 21.4 percent reduction in HIV incidence over two years. Lottery incentives appear to be particularly effective in tar- geting individuals with ex ante risky sexual behavior, consistent with the hypothesis that lotteries are more valued by individuals willing to take risks.